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Demco A-Frame Couplers
Demco Brake Actuator Couplers

Demco





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Expert Answers about Demco

  • How To Check if Trailer Surge Brakes Are Working Properly On Tandem Axle Boat Trailer
  • Checking the brakes can be done in two ways. The easiest way is to raise one side of the trailer and spin the wheels while someone applies the surge brakes at the coupler. The better way would be to remove each of the wheels and brake drums and activate the brakes while making sure the wheel cylinders and brake assemblies are functioning properly. After this the first thing I would do is bleed the brakes using the trailers surge coupler to force the fluid from the brake lines and make...
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  • Where Can VIN Be Found On Travel Trailer
  • The trailer A-Frame tongue is the first place to check. Look for a ID plate affixed to the frame near the coupler. If the ID plate isn't evident there, check the front storage compartment and look over any exposed frame members in that area. On some travel trailers, The ID plate is actually inside the trailer, inside a storage cabinet.
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  • What Brake Fluid Should be Used in Surge Brake Actuators
  • DOT 3 or DOT 4 brake fluid is recommended for Demco brake actuators like the # 8605001. You should never use DOT 5 as it will wear out seals very quickly.
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  • Recommendation for Installation of a Brake Mounting Flange on a Trailer Spindle and Axle
  • Welding a mounting flange, possible item # 4-35, is a very precise installation. The flanges need to be installed square and concentric to the hub and drum assembly and each other. If the flange is installed incorrectly rapid brake lining wear, improper braking, trailer dog legging, bearing failure, rapid tire wear and, worst of all, weakening of the axle can occur. Usually special jigs are used to install the flange. The jig will keep the flange square and concentric to the axle and...
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  • Troubleshooting Surge Brakes Locking up When in Reverse
  • With surge brakes, you have a brake actuator applying the needed pressure to the brakes but to be able to back up you will need to have a manual lockout or an electric lockout solenoid, like # T4748800, which will close when you shift the vehicle into reverse, allowing the trailer to be backed up. You may also need a solenoid cover like the Titan # T4835800183, depending on what brake actuator you currently have. Typically surge brakes are found on boat trailers, and commonly the...
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  • Serial Number Location On Enclosed Trailer
  • The serial number or vehicle identification number for a trailer is normally on a sticker or plate located on the tongue or the front of the trailer. The plate will list the trailer capacity and will usually contain other information such as the trailer's GVWR, the recommended tire size and the manufacturer name.
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  • How to Bleed Trailer Surge Brakes
  • I attached a video that details how to bleed surge brake actuators for you to check out. First top off the master cylinder with appropriate fluid. Next you will want to pump the fluid from the master cylinder. You can do this by unbolting the plate that holds the lever in place and then use that lever to actuate the master cylinder and force the fluid through. On some units, you will have to manually activate it at the point where the hitch ball moves in and out. The model in the video...
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  • Parts Needed to Replace Brakes, Brake Lines and Actuator on Tandem Axle Boat Trailer
  • We have everything that you will need to replace the brakes, brake lines and the actuator on your tandem axle boat trailer, but to make sure we recommend the correct parts for your trailer, we will need a little more information. For a brake line kit, I recommend the Demco Hydraulic Brake Line Kit for Tandem Axle Trailers, # DM5428. This is our most economical hydraulic brake line kit and it uses the standard brake line fittings, so it will be compatible with all hydraulic brake assemblies...
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  • How To Bleed Trailer Brakes
  • You are in luck! We happen to have a video on the proper procedure for bleeding trailer brakes. I have attached the video below as well as outline the method here for you. First top off the master cylinder with appropriate fluid. Next you will want to pump the fluid from the master cylinder. You can do this by unbolting the plate that holds the lever in place and then use that lever to actuate the master cylinder and force the fluid through. On some units, you will have to manually activate...
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  • How to Reset Breakaway Cable of Atwood Surge Brake Actuator
  • If your emergency/breakaway brake cable has been pulled slightly that would be why the brakes aren't releasing like they are supposed to. You need to reset it so that the brakes will release like they should. To reset the breakaway cable on the Atwood Hydraulic Brake Actuator, item # 84132, you will need to feed the cable back through the opening in the top of the housing so the push rod can be properly released into the master cylinder. Once this is done, pressure from the master...
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  • Removing Surge Coupler-Actuated Brakes from Mc Clain Boat Trailer
  • If you want to deactivate the hydraulic brakes on your boat trailer, you can certainly do so. The simplest way to do this would be to drain the brake fluid from the lines by disconnecting the brake lines from the wheel cylinders and allowing the fluid to drain. You'd then immobilize the articulating portion of the coupler by drilling holes in either side and sliding a bolt through to prevent the coupler from compressing. A better long term option would be to remove the coupler and replace...
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  • Fit of Demco # DM8104311 Hydraulic Brake Actuator
  • The Demco # DM8104311 is compatible with 3 inch wide straight trailer tongues. You can see our return policy by clicking the provided link.
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  • Measurements of Demco Hydraulic Brake Actuator at Openings for Trailer Frame
  • The Demco Hydraulic Brake Actuator # DM8609502 measures 4 inches at the smaller opening and 15.313 inches at the larger opening. This actuator is for drum brakes, is rated for 8,000 pounds towing, and is made in the USA.
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  • Hydraulic Disc or Drum Trailer Brakes for 10 Inch Wheels
  • We have several options for trailer brakes that will fit a 10 inch wheel. For a 10 inch wheel you will need a 8-1/2 inch hub and drum assembly such as # T1544500042 which has a 5 on 4-1/2 bolt pattern. Then for hydraulic drum brakes we have just one option, # T4442000 for the right side and # T4442100 for the left side. These are designed for 3,000 pound axles. For disc brakes we have the following options: For 2,000 pound axles we have # K2HR2D or # K2HR2E. For 3,500 pound axles...
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  • Key Differences Between Disc Brake and Drum Brake Trailer Coupler and Brake Actuators
  • Drum brake actuators and disc brake actuators use different master cylinders. A disc brake actuator producer a higher psi than a drum brake actuator so the fittings will be a little different as well. The drum brake master cylinder will have a check valve in it that reduces the amount of psi the system puts out. The disc brake models do not have this valve because more pressure is needed to actuate disc brakes The problem could be air in the lines and/or pistons in the calipers that...
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  • Trailer Surge Brake Coupler Operation
  • I am not sure what surge coupler you have on your ditch witch trailer, but I think I can help with the function. Surge brakes use the momentum of the vehicle and the hitch ball to activate stopping by pushing against the plunger of the master cylinder inside the coupler. This is like hitting a brake pedal. The amount of force is transferred into the braking pressure of the hydraulic brake system. So when pulling it has no pressure (like having your foot off the brake pedal) and when...
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  • Recommended Brake Assemblies for Karavan Boat Trailer with 3500 lb Axle
  • For your brake assemblies, I recommend the Demco Hydraulic Brake Kit - Free Backing - Galvanized - 10" - Left/Right Hand Assemblies - 3.5K # 40716-15. These galvanized assemblies will work very well for saltwater or freshwater use, resisting corrosion. The free backing design allows you to back up without using the lockout on your coupler. This will absolutely fit your 3500 lb axle. For your Bearing Buddies, bearings, and seals, you very likely have the standard size 84 spindle...
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  • Replacement Hydraulic Drum Brakes and Hubs for E-Z Loaded Boat Trailer
  • Demco free-backing 10 x 2-1/4-inch galvanized hydraulic brakes # 40715 and # 40716 are intended for a 3500-lb axle with a 4-on-4 brake flange mounting pattern. These are a great choice for replacements for your trailer's one axle. These brakes work with 13- to 15-inch wheels. As long as you've matched your axle rating, drum size and mounting pattern these brakes should be perfect for your boat trailer. E-Z Loader trailers are pretty popular and they use readily available parts. If you...
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  • Coupler Lock Recommendation for Use with Demco Channel Tongue Trailer Coupler
  • Yes the coupler part # DM13689-52 that you referenced is lockable. For a pin style lock the part # 28012 would work well. Or for a lock that goes around the coupler opening the part # DT25013KA would be a great option. I attached review videos for both locks.
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  • What Braking Assemblies do I Need for Karavan Tandem Axle
  • If the bolt pattern on your axles, for the backing plate, is 2-3/4 inch on center , both of these braking assemblies would fit your 10 inch x 2-1/4 inch trailer brake assemblies. Part # 40715 and # 40716 are what I would recommend. These are the left and right hand side brake assemblies. Since you are going to be backing up an incline you want the least amount of reverse braking which is why I recommend these over the other. The shoes for these assemblies are part # BP04-126. The...
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  • How Do I Know If I Have Free-Backing Brakes?
  • Your trailer must have free backing brakes if you have never used the surge brake actuating coupler reverse lockout. If you did not have free backing brakes, your brakes would most likely brake even if they didn't lock up when you back up because of the trailer weight pushing against the hitch ball. The only way to know for sure is to pull your hub/drum off the spindle and look at the hydraulic cylinder. Free-backing brakes like # AKFBBRK-7R-D will have only one pin coming out and...
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  • Recommendation on a Surge Coupler that is Rated to Work on a Trailer w/ Disc Brakes
  • I found a surge coupler that will work well on your trailer. However, the part that you referenced, # DM8204011, is designed only to work with drum brake systems. Disc brake systems need higher psi for the calipers to activate the brakes and drum surge coupler cannot supply the correct pressure. I recommend the Demco Hydraulic Brake Actuator w/ Drop for Disc Brakes, # DM8204311. This surge coupler is almost identical to the one you referenced, except it is rated to be used with disc...
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  • Can Free-Backing Brakes Replace Non-Free-Backing Breaks on 2001 EZ Loader Boat Trailer
  • You can use free-backing brake assemblies on your trailer in place of the existing non-free-backing brakes. For your 2001 EZ Loader boat trailer I recommend the Demco Hydraulic Drum Brake Assemly, Free Backing, Galvanized, for 10 Inch Brakes # 40715 for the right- hand side and # 40716 for the left-hand side. The galvanized steel will resist rust, making these assemblies great for your boat trailer. I have attached an installation video of these brakes for you. Another great option is...
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  • Determining If Surge Brake Actuator Has Lockout or If Brakes are Free-Backing
  • The only way to turn a surge brake actuator "off" is to engage a lockout on the actuator. Some actuators have manual lockouts, others have electric lockouts, and some have no way to lock out the actuator. Typically, free-backing brakes are used with actuators that have no lockout. As long as the trailer brakes engaging when your tow vehicle is stopping, the brakes are working correctly. I have attached photos showing a manual lockout and electric lockout to help you determine if your...
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  • Measurement Of The Adjustment Holes On Demco Lunette Ring and Compatibility With Curt Channel Mount
  • Yes, the Demco Lunette Ring - Adjustable Channel Mount - 3" Diameter - Black - 25,000 lbs, # DM09557-81 should be compatible with the Channel Style Adjustable Ballmount - 2" & 2-5/16" Balls - 14,000 lbs, # C45900 but you will be limited by the 14,000 lb capacity of the mount for towing. The Demco lunette ring has 2 inch on center holes and the Curt mount has 1 inch on center adjustability. If you want the lockable pins, I recommend the Curt Lock Set for Adjustable Channel-Style Mounts...
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  • Can a Weld-On A-Frame Trailer Coupler be Bolted On Instead of Welded
  • The A-frame couplers we carry, like # 12660-97SP, are weld-on applications and cannot be bolted on to a trailer frame. Any welding should be done by a qualified welder in a shop that works on trailers. The coupler you have reference accepts a 2-5/16 inch diameter ball. I have included a link to all of the A-frame coupler options for you to view.
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  • What are the Correct Replacement Wheel Cylinders for Demco Hydraulic Trailer Brakes # 40716
  • If you have Redline brakes (part # 40716 is actually Demco), then you will need to use Redline Wheel Cylinder, # BP17-030 (left) and # BP17-020 (right). The correct replacement wheel cylinder for your hydraulic trailer brake assemblies is determined by the brand and size of brake assembly that is on your trailer.
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  • Dimensions and Mounting Hole Spacing of Demco Channel Tongue Trailer Coupler # 12564
  • Yes, the Demco Channel Tongue Trailer Coupler # 12564 that you referenced does accept a 2-inch hitch ball and mounts to a 3-inch-wide trailer tongue. It's mounting hole spacing is indeed 3-inches and it offers a 10,000-lb weight capacity. You'll need to re-use or replace your installation hardware as this is not included with this zinc-plated coupler.
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  • Truck and Trailer Shakes When Brakes Are Applied
  • When it comes to your trailer shaking when the brakes are applied, it sounds like you may have a clogged brake line. In this case I recommend bleeding the brakes. I have included a video which goes over the process. I would also check your brake adjustment. After completing these steps, if you are still experiencing issues send me an email and we can continue the troubleshooting process.
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  • Stainless Steel Rotor, Caliper, and Additional Components for 8,000 Pound Dexter Axles
  • We have a couple different options for you to upgrade the components on your boat trailer. For a kit that comes with a hub and rotor, you can use the Kodiak Disc Brake Kit, 13 Inch Hub/Rotor with 8 on 6-1/2 Wheel Bolt Pattern for 8,000 Pound Dexter Axles # K2HR89DDS. This kit comes with dacromet-plated, cast iron rotor-and-hub assemblies, stainless steel calipers, stainless steel caliper mounting brackets, and stainless steel mounting bolts. The bearings, races, and seal measurements...
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